Tire performance is an important concern. Manufacturers and tire developers, as well as others in the industry, find that the methods for testing (1) tire characteristics; (2) performance of tire-vehicle systems, and (3) performance of components of tire-vehicle systems are of substantial interest.
The footprint of a tire has a substantial influence on tire performance, including tire wear, driving stability, noise, and ride comfort. Accordingly, there is interest in measurement of the qualities of the footprint of a tire.
Various tests have been designed to determine the footprint of a tested tire. These tests involve means of observing or sensing the footprint as it rolls over the measurement surface. Tests conducted outdoors on vehicles driving over measurement surfaces require expensive test instrumentation and may have limited repeatability due to the variability of driving conditions. Such testing is therefore expensive and time consuming. In order to avoid the expense and time of outdoor tire test procedures, some indoor tire test equipment has been developed. Indoor test equipment has mostly been limited to footprint testing of non-rolling tires or at low rolling speeds. Tire operation, however, may be at speeds other than at low speeds, such as, without limitation, high speeds, such as, without limitation, highway speeds. The current methods and apparatuses are not readily adaptable to use at different speeds or use at different operating conditions, such as highway speed. It remains desirable to develop apparatuses and methods for measurement of the qualities of the footprint of a tire at high speeds.